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You searched for: subject:"photovoltaic cells"
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[texts]8. Electronics IJECE Modeling Of Photovoltaic Panel Avinash
As per the present scenario lot of power shortages are there all over the world especially country like India the grid transferring problem is also high. Almost the power from the fossil fuels is becoming so less. There is increasing demand for the use of power from renewable based energy sources such as solar, wind, biomass, tidal etc which does not cause any damage to the environment. Unlike conventional generation the solar energy is available at no cost and is pollution free...
Keywords: Cost Benefit Analysis; Photovoltaic Cells; Photovoltaic Effects
Downloads: 6
[texts]8. Electronics IJECE Modeling Of Photovoltaic Panel Avinash
As per the present scenario lot of power shortages are there all over the world especially country like India the grid transferring problem is also high. Almost the power from the fossil fuels is becoming so less. There is increasing demand for the use of power from renewable based energy sources such as solar, wind, biomass, tidal etc which does not cause any damage to the environment. Unlike conventional generation the solar energy is available at no cost and is pollution free...
Keywords: Cost Benefit Analysis; Photovoltaic Cells; Photovoltaic Effects
Downloads: 6
[texts]Solid-state non-volatile electronically programmable reversible variable resistance device - NON
A solid-state variable resistance device (10) whose resistance can be repeatedly altered by a control signal over a wide range, and which will remain stable after the signal is removed, is formed on an insulated layer (14), supported on a substrate (12) and comprises a set of electrodes (16a, 16b) connected by a layer (18) of material, which changes from an insulator to a conductor upon the injection of ions, covered by a layer (22) of material with insulating properties which permit the passage...
Keywords: ELECTRIC POTENTIAL; LOADS (FORCES); PHOTOVOLTAIC CELLS; SOLAR ARRAYS; PATENTS
Downloads: 122
[texts]Comparison of the Effects of using Tygon Tubing in Rocket Propulsion Ground Test Pressure Transducer Measurements - Farr, Rebecca A.
This paper documents acoustics environments data collected during liquid oxygen- ethanol hot-fire rocket testing at NASA Marshall Space Flight Center in November- December 2003. The test program was conducted during development testing of the RS-88 development engine thrust chamber assembly in support of the Orbital Space Plane Crew Escape System Propulsion Program Pad Abort Demonstrator. In addition to induced environments analysis support, coincident data collected using other sensors and meth...
Keywords: SOLAR ARRAYS; LENSES; PHOTOVOLTAIC CELLS; CONCENTRATORS; SPACE MISSIONS; HARDWARE
Downloads: 132
[texts]Research to the Typical Defects of Crystalline Silicon Photovoltaic Cells based on EL Images
According to the electroluminescent imaging mechanism ofcrystalline silicon photovoltaic cells, EL images of four kindsof the typical defects that happened with high frequency inthe course of the production in crystalline siliconphotovoltaic cells, such as, black core, cracks, broken gateand over welding, etc, were analyzed with some emphasis inthis articleon the aspects ofthe characteristic, productionmechanism, harm and resolution of those images, then thesolution to defects is applied to prod...
Keywords: Crystalline Silicon Photovoltaic Cells; Electroluminescence Images; Defect; Analysis; Diagnose
Downloads: 21
[texts]Geology and geochemistry of sulfide and sulfate deposition - Holser, W. T
Factors contributing to the geology and geochemistry of sulfide and sulfate deposition are discussed. The age curves of sulfur and oxygen isotopes in marine sulfate are assessed.
Keywords: ENCAPSULATING; STATISTICAL ANALYSIS; MANUFACTURING; PHOTOVOLTAIC CELLS; PRODUCTIVITY; FAILURE; MODULES; PROCESS CONTROL (INDUSTRY); QUALITY CONTROL; RELIABILITY
Downloads: 125
[texts]Minimum-fuel turning climbout and descent guidance of transport jets - Neuman, F.
The complete flightpath optimization problem for minimum fuel consumption from takeoff to landing including the initial and final turns from and to the runway heading is solved. However, only the initial and final segments which contain the turns are treated, since the straight-line climbout, cruise, and descent problems have already been solved. The paths are derived by generating fields of extremals, using the necessary conditions of optimal control together with singular arcs and state constr...
Keywords: HEAT TRANSMISSION; PHOTOVOLTAIC CELLS; SOLAR CELLS; ENERGY CONVERSION EFFICIENCY; GROOVES; LIGHT TRANSMISSION; TRANSPARENCE
Downloads: 109
[texts]The Supercritical Pile Model for GRBs - Kazanas, D
We present the spectral and temporal radiative signatures expected within the ''Supercritical Pile'' model of Gamma Ray Bursts (GRB). This model is motivated by the need for a process that provides the dissipation necessary in GRB and presents a well defined scheme for converting the energy stored in the relativistic protons of the Relativistic Blast Waves (RBW) associated with GRB into radiation; at the same time it leads to spectra which exhibit a peak in the burst nuF(sub nu) distribution at ...
Keywords: AIRSHIPS; HIGH ALTITUDE; ENERGY CONVERSION EFFICIENCY; THERMOELECTRIC GENERATORS; THERMOELECTRIC MATERIALS; PHOTOVOLTAIC CELLS; MODULES; ESTIMATING
Downloads: 112
[texts]Assessment of the international workshop on CdS solar cells - Boer, K. W
General problems relating to the basic understanding of CdS/Cu2S solar cell operation, to material aspects of the cell and to manufacturing methods and cell engineering are discussed.
Keywords: CRYSTAL GROWTH; RIBBONS; SEMICONDUCTING FILMS; SILICON; PHOTOVOLTAIC CELLS; PRODUCTION ENGINEERING; SOLAR ARRAYS
Downloads: 128
[texts]Epitaxial technology for low cost solar cells - Kressel, H.
Epitaxial solar cell structures on low cost silicon substrates are compared to direct diffusion substrates. Dislocation density in the epitaxial layers is found to be significantly lower than that of the substrate material. The saturation current density of diodes epitaxially formed on the substrate is commonly 2 to 3 orders of magnitude lower than for diodes formed by direct diffusion. Solar cells made epitaxially are substantially better than those made by direct diffusion into similar materia...
Keywords: PHOTOVOLTAIC CELLS; SOLAR ENERGY CONVERSION; SYSTEMS ANALYSIS; COST ESTIMATES; ELECTRIC POWER SUPPLIES
Downloads: 91
[texts]Feasibility investigation of growing gallium arsenide single crystals in ribbon form - Richardson, D. L
Polycrystalline GaAs ribbons have been grown in graphite boats by passage of a wide zone through B2O3 encapsulated feed stock, confined by a quartz cover plate. By controlling the heat flow in the graphite boat and controlling the zoning rate, large grained, single phase polycrystalline samples with directional solidification and good thickness control were achieved. Arsenic vaporization was effectively suppressed at the melting point of GaAs by the B2O3 moat and 3 atmospheres of pressure...
Keywords: ENERGY CONVERSION EFFICIENCY; PHOTOVOLTAIC CELLS; SOLAR COLLECTORS; COMPUTER PROGRAMMING; SILICON; SOLAR ENERGY CONVERSION; THERMAL ABSORPTION
Downloads: 132
[texts]CdS thin film solar cells for terrestrial power - Shirland, F. A
The development of very low cost long lived Cu2S/CdS thin film solar cells for large scale energy conversion is reported. Excellent evaporated metal grid patterns were obtained using a specially designed aperture mask. Vacuum evaporated gold and copper grids of 50 lines per inch and 1 micron thickness were adequate electrically for the fine mesh contacting grid. Real time roof top sunlight exposure tests of encapsulated CdS cells showed no loss in output after 5 months...
Keywords: PHOTOVOLTAIC CELLS; RESEARCH AND DEVELOPMENT; RESEARCH MANAGEMENT; LOW COST; PERFORMANCE TESTS; SOLAR CELLS; SOLAR ENERGY CONVERSION
Downloads: 135
[texts]Ternary compound thin film solar cells - Kazmerski, L. L
A group of ternary compound semiconductor (I-III-VI2) thin films for future applications in photovoltaic devices is proposed. The consideration of these materials (CuInSe2, CuInTe2 and especially CuInS2) for long range device development is emphasized. Much of the activity to date has been concerned with the growth and properties of CuInX2 films. X-ray and electron diffraction analyses, Hall mobility and coefficient, resistivity and carrier concentration variations with substrate and film temper...
Keywords: SOLAR CELLS; SPUTTERING; THIN FILMS; CADMIUM SULFIDES; COPPER SULFIDES; PHOTOVOLTAIC CELLS; PRODUCTION ENGINEERING
Downloads: 150
[texts]Inertial navigation/calibration/precise time and frequency capabilities - Galloway, L. M.
The Aerospace Guidance and Metrology Center was conceived in 1959 to be the US Air Force Inertial Navigation and Metrology Center. This paper will show the mission capabilities of the Inertial Navigation Maintenance Center and the Air Force Measurement and Standards Laboratory. Highlighted will be the precise time and frequency program developed by AGMC to support Air Force precise time and frequency requirements worldwide...
Keywords: CONFERENCES; UTILITIES; FLAT PLATES; SOLAR ARRAYS; ELECTRIC NETWORKS; FAILURE ANALYSIS; PHOTOVOLTAIC CELLS; REFINING; SILICON; THIN FILMS
Downloads: 103
[texts]Reactively sputtered thin film photovoltaic devices - Hsieh, E. J
The feasibility of a reactively sputtered thin film CdS - Cu2S solar cell is proven. Identification of the reactively sputtered Cu2S film is made by X-ray diffractometer and spectro-transmission measurements. Because of its simplicity, economical use of material, and high yield, the reactive sputtering process promises to be a low cost method for producing CdS - Cu2S solar cells.
Keywords: ENERGY CONVERSION EFFICIENCY; PERFORMANCE TESTS; PHOTOVOLTAIC CELLS; ELECTROMAGNETIC ABSORPTION; RADIATION MEASUREMENT; SOLAR ENERGY CONVERSION
Downloads: 103
[texts]Finite element methods for integrated aerodynamic heating analysis - Peraire, J
Over the past few years finite element based procedures for the solution of high speed viscous compressible flows were developed. The objective of this research is to build upon the finite element concepts which have already been demonstrated and to develop these ideas to produce a method which is applicable to the solution of large scale practical problems. The problems of interest range from three dimensional full vehicle Euler simulations to local analysis of three-dimensional viscous laminar...
Keywords: DOCUMENTS; PROCESS CONTROL (INDUSTRY); PHOTOVOLTAIC CELLS; PHOTOVOLTAIC CONVERSION; QUALITY CONTROL; CONTRACTORS; COST EFFECTIVENESS; CRITERIA; INSTALLING; MANUFACTURING
Downloads: 126
[texts]Low cost AMOS solar cell development - Stirn, R. J
Recent developments at JPL have demonstrated that high conversion efficiencies are found with GaAs metal semiconductor solar cells when a particular heat treatment processing step is used to introduce an interfacial layer between the metal and the semiconductor. The new cell, called AMOS (Antireflection-Coated Metal-Oxide-Semiconductor), has open circuit voltages of 0.68-0.72 volts and efficiencies of 15% under terrestrial sunlight, as compared to values of 0.45-0.48 volts and 10%, respectively,...
Keywords: GLASS; SILICON JUNCTIONS; SOLAR CELLS; ENERGY CONVERSION EFFICIENCY; PHOTOVOLTAIC CELLS; POLYCRYSTALS; SINGLE CRYSTALS
Downloads: 147
[texts]Applied research on 2-6 compound materials for heterojunction solar cells - Bube, R. H
Several II-VI heterojunctions show promise for photovoltaic conversion of solar energy. The three of greatest interest are p-CdTe/n-CdS, p-CdTe/n-ZnSe, and p-ZnTe/n-CdSe. Several p-CdTe/n-CdS heterojunction cells have been prepared by close spaced transport deposition of p-CdTe on single crystal n-CdS, and by two source vacuum evaporation of n-CdS on single crystal p-CdTe. Both types of cells, in an experimental stage, are quite comparable, exhibiting values of quantum efficiency between 0.5 and...
Keywords: MATHEMATICAL MODELS; PHOTOVOLTAIC CELLS; SILICON; SOLAR COLLECTORS; ENERGY CONVERSION EFFICIENCY; SOLAR ENERGY CONVERSION; STRUCTURAL DESIGN CRITERIA
Downloads: 129
[texts]Direct solar energy conversion for large scale terrestrial use - Boeer, K. W.
Various techniques to increase the open circuit voltage are being explored. It had been previously observed that cells made on CdS deposited from a single source gave a consistently higher V sub oc. Further tests have now shown that this effect may in fact relate to differences in source and substrate temperatures. The resulting differences in CdS structure and crystallinity are being documented. Deposits of mixed CdS and ZnS are being produced and will be initially made into cells using the con...
Keywords: MILITARY TECHNOLOGY; PHOTOVOLTAIC CELLS; RESEARCH MANAGEMENT; ENERGY SOURCES; SOLAR CELLS; SOLAR ENERGY CONVERSION
Downloads: 105
[texts]Investigation of thin film solar cells based on Cu2S and ternary compounds such as CuInS2 - Loferski, J. J
Production and characterization in thin film form of Cu2S and related Cu compounds such as CuInS2 for photovoltaic cells are examined. The low cost process technology being reported, namely the sulfurization method, is capable of producing films on various substrates. Cathodoluminescence is being used as a diagnostic tool to identify Cu(x)S and CuInS2 compounds. Also, single crystals of CuInS2 are being prepared and it is contemplated that p-n junctions will be made in such crystals.
Keywords: PARABOLIC REFLECTORS; PHOTOVOLTAIC CELLS; SOLAR COLLECTORS; COST EFFECTIVENESS; ENERGY CONVERSION EFFICIENCY; SILICON; SOLAR ENERGY CONVERSION
Downloads: 268
[texts]Deep Space Telecommunications Systems Engineering - NON
Descriptive and analytical information useful for the optimal design, specification, and performance evaluation of deep space telecommunications systems is presented. Telemetry, tracking, and command systems, receiver design, spacecraft antennas, frequency selection, interference, and modulation techniques are addressed.
Keywords: ELECTRIC POTENTIAL; FLAT PLATES; PHOTOVOLTAIC CELLS; POWER CONDITIONING; CLIMATE; COMPUTERIZED SIMULATION; ENERGY CONVERSION EFFICIENCY; NORMALIZING (STATISTICS)
Downloads: 2,136
[texts]American Space History: Legacies, Questions, and Opportunities for Future Research - Siddiqi, Asif A
In the 35 years since astronauts Neil A. Armstrong and Buzz Aldrin set foot on the Moon, no space achievement has quite captured people s imaginations as Apollo. Thirty-five years after that singular event, the specter of Apollo still looms large as a benchmark for all that came later. In the context of the current inertia of the American space program-the Space Shuttle temporarily grounded while astronauts take to orbit in Russian rockets for unimaginative tours of the International Space Stati...
Keywords: SOLAR ARRAYS; SOLAR ENERGY; SOLAR POWERED AIRCRAFT; SUNLIGHT; PHOTOVOLTAIC CELLS; SOLAR CELLS; INDUSTRIES; ORGANIZATIONS; RESEARCH AIRCRAFT
Downloads: 270
[texts]Evaluation of a new concept for reducing free-stream turbulence in wind tunnels - Wigeland, R. A.
The feasibility of using a 45 deg-honeycomb for improving the flow quality in wind tunnels was investigated. The results of the experiments indicate that the turbulence levels in a wind tunnel using the 45 deg-honeycomb would be comparable to those obtainable using a conventional honeycomb, i.e., a honeycomb which is positioned normal to the mean flow in the settling chamber. However, this is true only when a 45 deg-screen is mounted immediately downstream of the honeycomb, and when some distanc...
Keywords: FORMING TECHNIQUES; PHOTOVOLTAIC CELLS; SOLAR CELLS; ELECTRIC CONTACTS; SEMICONDUCTOR DEVICES; SILVER COMPOUNDS; WAFERS
Downloads: 190
[texts]Quality requirements for reclaimed/recycled water - Janik, Daniel S.
Water used during current and previous space missions has been either carried or made aloft. Future human space endeavors will require some form of water reclamation and recycling. There is little experience in the U.S. space program with this technology. Water reclamation and recycling constitute engineering challenges of the broadest nature that will require an intensive research and development effort if this technology is to mature in time for practical use on the proposed U.S...
Keywords: HOMOJUNCTIONS; INDIUM PHOSPHIDES; PHOTOVOLTAIC CELLS; RADIATION EFFECTS; SPACECRAFT POWER SUPPLIES; EXTRATERRESTRIAL RADIATION; ION IMPLANTATION; LIQUID PHASE EPITAXY; VAPOR DEPOSITION
Downloads: 112
[texts]Fan Stall Flutter Flow Mechanism Studied - Lepicovsky, Ja
Modern turbofan engines employ a highly loaded fan stage with transonic or low-supersonic velocities in the blade-tip region. The fan blades are often prone to flutter at off-design conditions. Flutter is a highly undesirable and dangerous self-excited mode of blade oscillations that can result in high-cycle fatigue blade failure. The origins of blade flutter are not fully understood yet. Experimental data that can be used to clarify the origins of blade flutter in modern transonic fan designs a...
Keywords: ATMOSPHERIC PRESSURE; SOLAR ARRAYS; SPRAYERS; VAPOR DEPOSITION; THIN FILMS; PHOTOVOLTAIC CELLS; AIR MASSES; TECHNOLOGY UTILIZATION; SUBSTRATES; SOLAR CELLS
Downloads: 99
[texts]Acoustical properties of highly porous fibrous materials - Lambert, R. F
Highly porous, fibrous bulk sound absorbing materials are studied with a view toward understanding their acoustical properties and performance in a wide variety of applications including liners of flow ducts. The basis and criteria for decoupling of acoustic waves in the pores of the frame and compressional waves in the frame structure are established. The equations of motion are recast in a form that elucidates the coupling mechanisms...
Keywords: POLYMERIZATION; SOLAR ARRAYS; STOICHIOMETRY; SEMICONDUCTORS (MATERIALS); SILICON; SILICON POLYMERS; SOLAR ENERGY CONVERSION; ENERGY POLICY; LOW COST; MASS SPECTROSCOPY; PHOTOVOLTAIC CELLS
Downloads: 212
[texts]Atmospheric Fragmentation of the Gold Basin Meteoroid as Constrained from Cosmogenic Nuclides - Welten, K. C.
Since the discovery of the Gold Basin L4 chondrite shower almost ten years ago in the northwestern corner of Arizona, many thousands of L-chondrite specimens have been recovered from an area of approx.22 km long and approx.10 km wide. Concentrations of cosmogenic 14C and 10Be in a number of these samples indicated a terrestrial age of approx.15,000 years and a large pre-atmospheric size [1]. Additional measurements of cosmogenic Be-10, Al-26, Cl-36, and Ca-41 in the metal and stone fractions of ...
Keywords: MIR SPACE STATION; SPACECRAFT POWER SUPPLIES; PHOTOVOLTAIC CELLS; INTERNATIONAL COOPERATION; RUSSIAN SPACE PROGRAM; SOLAR ARRAYS; UPGRADING; ACCELERATED LIFE TESTS
Downloads: 92
[texts]Non-reflecting boundary conditions for the compressible Navier-Stokes equations - Abarbanel, S.
A small perturbation analysis, in the long wavelength regime, is used to obtain the downstream boundary condition for the pressure for the flow over a flat plate. The methodology is extendable to other geometries. Numerical results for high Reynolds number laminar flows show great improvement in convergence rate to steady state as well as the quality of the results.
Keywords: CHEMICAL BONDS; ADHESION; ADHESIVE BONDING; INTERFACIAL ENERGY; DELAMINATING; ELECTRONIC MODULES; ENCAPSULATING; FLAT PLATES; INTERFACES; PHOTOVOLTAIC CELLS; SILICONES; SOLAR ARRAYS
Downloads: 195
[texts]Proceedings of the fourth photovoltaic specialists conference. volume i- radiation effects on solar cells and photovoltaic devices - NON
Conference on radiation resistance and damage in silicon solar cells and photovoltaic devices
Keywords: CONFERENCES; RADIATION RESISTANCE; SILICON; SOLAR CELL; PHOTOVOLTAIC CELLS; PHOTOVOLTAIC EFFECT; RADIATION EFFECTS; RADIATION TOLERANCE; SILICON; SOLAR CELLS; CONFERENCE; PHOTOVOLTAIC EFFECT
Downloads: 229
[texts]Mass distribution of orbiting man-made space debris - Bess, T. D
Three ways of producing space debris were considered, and data were analyzed to determine mass distributions for man-made space debris. Hypervelocity (3.0 to 4.5 km/sec) projectile impact with a spacecraft wall, high intensity explosions and low intensity explosions were studied. For hypervelocity projectile impact of a spacecraft wall, the number of fragments fits a power law. The number of fragments for both high intensity and low intensity explosions fits an exponential law...
Keywords: COPPER COMPOUNDS; TERNARY ALLOYS; INDIUM COMPOUNDS; SELENIUM COMPOUNDS; SOLAR CELLS; THIN FILMS; CRYSTAL GROWTH; PHOTOVOLTAIC CELLS; PRODUCTION ENGINEERING; SEMICONDUCTING FILMS
Downloads: 235
[texts]Suppression of biodynamic interference in head-tracked teleoperation - Lifshitz, S.
The utility of helmet-tracked sights to provide pointing commands for teleoperation of cameras, lasers, or antennas in aircraft is degraded by the presence of uncommanded, involuntary heat motion, referred to as biodynamic interference. This interference limits the achievable precision required in pointing tasks. The noise contributions due to biodynamic interference consists of an additive component which is correlated with aircraft vibration and an uncorrelated, nonadditive component, referred...
Keywords: CRITERIA; SOLAR RADIATION; ENVIRONMENT EFFECTS; PHOTOVOLTAIC CELLS; PHOTOVOLTAIC CONVERSION; CLOUD COVER; DOCUMENTS; RESIDENTIAL ENERGY; SENSITIVITY; SITE SELECTION
Downloads: 93
[texts]Shallow junction photovoltaic device program - Wichner, R
The technical feasibility of using the corona discharge technique as a means for producing efficient silicon solar cells is elaborated.
Keywords: DOPED CRYSTALS; SILICON JUNCTIONS; SOLAR ARRAYS; SOLAR ENERGY CONVERSION; COST EFFECTIVENESS; NEUTRON IRRADIATION; PHOTOVOLTAIC CELLS; PRODUCTION ENGINEERING
Downloads: 182
[texts]Fluorinated epoxy resins with high glass transition temperatures - Griffith, James R
Easily processed liquid resins of low dielectric constants and high glass transition temperatures are useful for the manufacture of certain composite electronic boards. That combination of properties is difficult to acquire when dielectric constants are below 2.5, glass transition temperatures are above 200 C and processability is of conventional practicality. A recently issued patent (US 4,981,941 of 1 Jan...
Keywords: ELECTRICITY; OXIDES; RARE GASES; SOLAR COLLECTORS; EMITTERS; ENERGY CONVERSION; NARROWBAND; PHOTOVOLTAIC CELLS; SOLAR ARRAYS; THERMAL ENERGY; GAS MIXTURES; NUCLEAR REACTORS
Downloads: 229
[texts]Interactive debug program for evaluation and modification of assembly-language software - Arpasi, D. J
An assembly-language debug program written for the Honeywell HDC-601 and DDP-516/316 computers is described. Names and relative addressing to improve operator-machine interaction are used. Features include versatile display, on-line assembly, and improved program execution and analysis. The program is discussed from both a programmer's and an operator's standpoint. Functional diagrams are included to describe the program, and each command is illustrated.
Keywords: AMORPHOUS SEMICONDUCTORS; SEMICONDUCTING FILMS; CHEMICAL REACTIONS; PLASMA JETS; SILANES; SILICON; AMORPHOUS SILICON; FEASIBILITY ANALYSIS; PHOTOVOLTAIC CELLS; PRODUCTION ENGINEERING
Downloads: 113
[texts]Focus determination for the James Webb Space Telescope Science Instruments: A Survey of Methods - Davila, Pamela S.
The James Webb Space Telescope (JWST) is a segmented deployable telescope that will require on-orbit alignment using the Near Infrared Camera as a wavefront sensor. The telescope will be aligned by adjusting seven degrees of freedom on each of 18 primary mirror segments and five degrees of freedom on the secondary mirror to optimize the performance of the telescope and camera at a wavelength of 2 microns...
Keywords: PHOTOVOLTAIC CELLS; INSULATORS; VACUUM DEPOSITION; SOLAR CELLS; MOON; LUNAR SURFACE; LUNAR ROCKS; OXYGEN; REGOLITH; EXTRACTION; THIN FILMS
Downloads: 115
[texts]Rechargeable metal hydrides for spacecraft application - Perry, J. L
Storing hydrogen on board the Space Station presents both safety and logistics problems. Conventional storage using pressurized bottles requires large masses, pressures, and volumes to handle the hydrogen to be used in experiments in the U.S. Laboratory Module and residual hydrogen generated by the ECLSS. Rechargeable metal hydrides may be competitive with conventional storage techniques. The basic theory of hydride behavior is presented and the engineering properties of LaNi5 are discussed to g...
Keywords: COST EFFECTIVENESS; ELECTRIC POWER PLANTS; PHOTOVOLTAIC CELLS; SITE SELECTION; ELECTROCHEMICAL CELLS; FUEL CELLS; HYDROELECTRIC POWER STATIONS; WINDPOWER UTILIZATION
Downloads: 104
[texts]Initial blood storage experiment - Surgenor, Douglas MACN
The possibility of conducting experiments with the formed elements of the blood under conditions of microgravity opens up important opportunities to improve the understanding of basic formed element physiology, as well as, contribution to improved preservation of the formed elements for use in transfusion. The physiological, biochemical, and physical changes of the membrane of the erythrocyte, platelet, and leukocyte was studied during storage under two specific conditions: standard blood bank c...
Keywords: FOCAL PLANE DEVICES; PHOTODIODES; TRENDS; INFRARED DETECTORS; INFRARED RADIATION; MERCURY CADMIUM TELLURIDES; PHOTOVOLTAIC CELLS; RANGEFINDING; SOLAR ARRAYS; HETEROJUNCTIONS; OPERATING TEMPERATURE
Downloads: 410
[texts]Bearing tester data compilation, analysis, and reporting and bearing math modeling - NON
The Shaberth bearing analysis computer program was developed for the analysis of jet engine shaft/bearing systems operating above room temperature with normal hydrocarbon lubricants. It is also possible to use this tool to evaluate the shaft bearing systems operating in cryogenics. Effects such as fluid drag, radial temperature gradients, outer race misalignments and clearance changes were simulated and evaluated...
Keywords: ACETATES; PRIMERS (COATINGS); ENCAPSULATING; ETHYLENE COMPOUNDS; PHOTOVOLTAIC CELLS; VINYL POLYMERS; ADHESIVES; AGING (MATERIALS); LOW COST; POTTING COMPOUNDS
Downloads: 144
[texts]Shuttle vertical fin flowfield by the direct simulation Monte Carlo method - Hueser, J. E.
The flow properties in a model flowfield, simulating the shuttle vertical fin, determined using the Direct Simulation Monte Carlo method. The case analyzed corresponds to an orbit height of 225 km with the freestream velocity vector orthogonal to the fin surface. Contour plots of the flowfield distributions of density, temperature, velocity and flow angle are presented. The results also include mean molecular collision frequency (which reaches 1/60 sec near the surface), collision frequency dens...
Keywords: ARRAYS; STABILITY; THIN FILMS; WEATHERING; AMORPHOUS SILICON; ENVIRONMENTAL QUALITY; IMPACT; RESEARCH AND DEVELOPMENT; COST EFFECTIVENESS; EXPOSURE; LIFE (DURABILITY); MODULES; PERFORMANCE TESTS; PHOTOVOLTAIC CELLS; RELIABILITY; SAFETY MANAGEMENT
Downloads: 53
[texts]Star Mapper - NON
A COSMIC (Computer Software Management and Information Center) program known as Skymap Star Catalog and Data Base provides a very accurate star map. The data assists Perkin Elmer Corporation in designing an optical system of proper size and field of view, and confirms the design integrity of star sensors which are very accurate and represent a major advance in optical technology. Perkin Elmer is the prime contractor for the optical telescope assembly of NASA's space telescope.
Keywords: DEPOSITION; SCANNING ELECTRON MICROSCOPY; LOW TEMPERATURE; X RAY DIFFRACTION; COPPER INDIUM SELENIDES; COPPER SULFIDES; FABRICATION; SUBSTRATES; THIN FILMS; MINERALS; PHOTOVOLTAIC CELLS; CHALCOGENIDES; SOLAR ARRAYS; THERMOGRAVIMETRY
Downloads: 26
[texts]The Properties of the local Interstellar Medium and the Interaction of the Stellar Winds of epsilon Indi and lambda Andromedae with the Interstellar Environment - Wood, Brian E.
We present new observations of the Ly alpha lines of Epsilon Indi (K5 5) and A Andromedae (G8 4-3 ) These data were obtained by the Goddard High Resolution Spectrograph (GHRS) on the Hubble Space Telescope. Analysis of the interstellar H 1 and D 1 absorption lines reveals that the velocities and temperatures inferred from the H 1 lines are inconsistent with the parameters inferred from the D 1 lines, unless the H 1 absorption is assumed to be produced by two absorption components...
Keywords: PHOTOVOLTAIC CELLS; PLASMA INTERACTIONS; SOLAR ARRAYS; SPACE PLASMAS; INTERNATIONAL SPACE STATION; ELECTRIC ARCS; ARC DISCHARGES; HIGH PRESSURE; CHARGE TRANSFER; ELECTRIC POTENTIAL
Downloads: 87
[texts]Ion Exchange Equilibrium and Kinetic Properties of Polyacrylate Films and Applications to Chemical Analysis and Environmental Decontamination - Tanner, Stephen P
One of the goals of the original proposal was to study how cross-linking affects the properties of an ion exchange material(IEM) developed at Lewis Research Center. However, prior to the start of this work, other workers at LERC investigated the effect of cross-linking on the properties of this material. Other than variation in the ion exchange capacity, the chemical characteristics were shown to be independent of the cross-linking agent, and the degree of cross-linking...
Keywords: THERMOPHOTOVOLTAIC CONVERSION; SUBSTRATES; SCATTERING; SAPPHIRE; REFLECTANCE; SOLAR CELLS; THERMAL ENERGY; ELECTRICITY; ENERGY CONVERSION EFFICIENCY; PHOTOVOLTAIC CELLS; THIN FILMS; EMITTERS; RARE EARTH ELEMENTS; OPTICAL THICKNESS
Downloads: 101
[texts]Reactive Brazing of Carbon-Carbon Composites to Titanium - Shpargel, Tarah
The Ti-metal/C-C composite joints were formed by reactive brazing with three commercial brazes, namely, Cu-ABA, TiCuNi, and TiCuSil. The joint microstructures were examined using optical microscopy, and scanning electron microscopy (SEM) coupled with energy dispersive spectrometry (EDS). The results of the microstructure analysis indicate solute redistribution across the joint and possible metallurgical bond formation via interdiffusion, which led to good wetting and spreading.
Keywords: PHOTOVOLTAIC CELLS; DEPOSITION; LOSSES; LOW TEMPERATURE; SOLAR FLUX; SPACECRAFT POWER SUPPLIES; MARS ROVING VEHICLES; MARS ENVIRONMENT; OPERATIONAL PROBLEMS; MARS MISSIONS; MARS SURFACE; MARS (PLANET); DUST
Downloads: 94
[texts]Erosive Burning Study Utilizing Ultrasonic Measurement Techniques - Furfaro, James A
A 6-segment subscale motor was developed to generate a range of internal environments from which multiple propellants could be characterized for erosive burning. The motor test bed was designed to provide a high Mach number, high mass flux environment. Propellant regression rates were monitored for each segment utilizing ultrasonic measurement techniques. These data were obtained for three propellants RSRM, ETM- 03, and Castor IVA, which span two propellant types, PBAN (polybutadiene acrylonitri...
Keywords: SPACE MISSIONS; MICROSATELLITES; ORBIT TRANSFER VEHICLES; SOLAR ELECTRIC PROPULSION; PROPULSION SYSTEM CONFIGURATIONS; INTERPLANETARY SPACECRAFT; SPACE EXPLORATION; SPACECRAFT POWER SUPPLIES; THIN FILMS; SOLAR ARRAYS; PHOTOVOLTAIC CELLS
Downloads: 99
[texts]Laser velocimetry in highly three-dimensional and vortical flows - Novak, C. J.
The need for experimentally determined 3-D velocity information is crucial to the understanding of highly 3-dimensional and vortical flow fields. In addition to gaining an understanding of the physics of flow fields, a correlation of velocity data is needed for advanced computational modelling. A double pass method for acquiring 3-D flow field information using a 2-D laser velocimeter (LV) is described...
Keywords: ECONOMICS; PHOTOVOLTAIC CELLS; PURITY; SILANES; SOLIDIFICATION; ENERGY CONSERVATION; MARKETING; PRODUCT DEVELOPMENT; SEMICONDUCTORS (MATERIALS); SILICON COMPOUNDS; SOLAR CELLS; COST EFFECTIVENESS; FLUIDIZED BED PROCESSORS
Downloads: 224
[texts]Introduction to design and fabrication of a long-life Stirling cycle cooler for space application. Phases 1 and 2: Engineering model - NON
A concept for a cryogenic refrigerator capable of long-life, reliable operation in space was proposed. The proposed concept was translated into a design phase in which the critical components were tested in dedicated fixtures and by the fabrication and test of a laboratory prototype with which to demonstrate the feasibility of the proposed concept. The engineering model program concept feasibility and addressed, the problems of efficiency, long life, and reliability...
Keywords: COST EFFECTIVENESS; ELECTRICAL RESISTIVITY; MINORITY CARRIERS; THIN FILMS; CRYSTAL GROWTH; CZOCHRALSKI METHOD; EFFICIENCY; FLOAT ZONES; PHOTOVOLTAIC CELLS; SILICON FILMS; SINGLE CRYSTALS; CARRIER LIFETIME
Downloads: 186
[texts]Magnetohydrodynamic Augmented Propulsion Experiment: I. Performance Analysis and Design - Litchford, R. J.
The performance of conventional thermal propulsion systems is fundamentally constrained by the specific energy limitations associated with chemical fuels and the thermal limits of available materials. Electromagnetic thrust augmentation represents one intriguing possibility for improving the fuel composition of thermal propulsion systems, thereby increasing overall specific energy characteristics; however, realization of such a system requires an extremely high-energy-density electrical power so...
Keywords: TECHNOLOGY UTILIZATION; PHOTOVOLTAIC CELLS; NANOTUBES; MICROELECTRONICS; FUEL CELLS; QUANTUM DOTS; PURITY; METAL IONS; PRODUCT DEVELOPMENT; WALLS; THIN FILMS; SOLAR CELLS; PROTONS
Downloads: 185
[texts]Undetected error probability and throughput analysis of a concatenated coding scheme - Costello, D. J
The performance of a proposed concatenated coding scheme for error control on a NASA telecommand system is analyzed. In this scheme, the inner code is a distance-4 Hamming code used for both error correction and error detection. The outer code is a shortened distance-4 Hamming code used only for error detection. Interleaving is assumed between the inner and outer codes. A retransmission is requested if either the inner or outer code detects the presence of errors...
Keywords: MARKETING; GOVERNMENT/INDUSTRY RELATIONS; PHOTOVOLTAIC CELLS; PROBABILITY DISTRIBUTION FUNCTIONS; SILANES; VAPOR DEPOSITION; POLYCRYSTALS; PRODUCT DEVELOPMENT; PRODUCTION ENGINEERING; REFINING; SEMICONDUCTORS (MATERIALS); SILICON; SOLAR CELLS; FLUIDIZED BED PROCESSORS
Downloads: 128
[texts]Advanced tube-bundle rocket thrust chamber - Kazaroff, John M.
An advanced rocket thrust chamber for future space application is described along with an improved method of fabrication. Potential benefits of the concept are improved cyclic life, reusability, and performance. Performance improvements are anticipated because of the enhanced heat transfer into the coolant which will enable higher chamber pressure in expander cycle engines. Cyclic life, reusability and reliability improvements are anticipated because of the enhanced structural compliance inheren...
Keywords: ESTIMATING; PHOTOELECTRIC CELLS; PHOTOVOLTAIC CELLS; RECEIVERS; SOLAR COLLECTORS; LASER POWER BEAMING; OPERATING TEMPERATURE; SATELLITE TRANSMISSION; SEMICONDUCTOR LASERS; STRUCTURAL DESIGN CRITERIA; HEAT RADIATORS; LENSES; PARABOLIC REFLECTORS
Downloads: 143
[texts]Firing squibs by low voltage capacitor discharge for spacecraft application - Earnest, J. E., Jr.
Low voltage capacitor discharge firing circuit to initiate hot bridgewire squibs for spacecraft applications
Keywords: ELECTRIC PROPULSION; PROTONS; SILVER ZINC BATTERIES; SYSTEMS ENGINEERING; TEMPERATURE; JUPITER (PLANET); PHOTOVOLTAIC CELLS; SOLAR CELLS; SPACECRAFT PROPULSION; ATLAS CENTAUR LAUNCH VEHICLE; ELECTRON FLUX DENSITY; ION ENGINES; MICROMETEOROIDS
Downloads: 385
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